(1) Field of the Invention
The present invention relates to a method of driving a light source and a display apparatus for performing the method. More particularly, the present invention relates to a method of driving a light source which significantly decreases a power consumption of the light source, and a display apparatus for performing the method.
(2) Description of the Related Art
In general, a liquid crystal display (“LCD”) apparatus has a thin thickness, light weight and low power consumption, relative to other types of display devices. Accordingly, the LCD apparatus is often used for manufacturing large-sized display devices, such as televisions, as well as monitors, a laptop computers and cellular phones, for example. The LCD apparatus typically includes an LCD panel that displays images by controlling light transmittance through a liquid crystal, and a light source apparatus disposed under the LCD panel to provide light to the LCD panel.
The light source apparatus includes a light source. The light source may be a cold cathode fluorescent lamp (“CCFL”), a hot cathode fluorescent lamp (“HCFL”) or a light emitting diode (“LED”), for example. The LED, in particular, is widely used, due advantages such as low power consumption and high color reproducibility as compared to other types of light sources. The light source apparatus using the LEDs as the light source typically includes LED strings that are connected in electrical parallel with each other. In addition, each LED string typically includes LEDs that are connected in electrical series with each other within the string.
Accordingly, the light source apparatus generally includes a plurality of the strings, connected in electrical parallel with each other, and a multi-channel current controlling circuit for providing a driving current to the strings.
The multi-channel current controlling circuit generally controls a resistance deviation between the LED strings, in attempts to control each driving current flowing through the LED strings such that they are substantially the same. However, to do so, the multi-channel current controlling circuit consumes a significant amount of power and thereby generates a substantial amount of heat to control the resistance deviation between the LED strings, and the heat generated by the multi-channel current controlling circuit causes a number of problems, such as damage to electronic elements in the LCD, for example.